A Santa Cruz man has been sentenced to 40 years in prison for killing his girlfriend, a prominent Santa Cruz attorney, while the pair were vacationing in Hawaii.

Gerald Galaway, 39, was sentenced Thursday to 20 years for manslaughter and 20 additional years for kidnapping in the 2011 slaying of Celestial Cassman, 35, who worked under contract as a deputy city attorney for Santa Cruz, Capitola and Half Moon Bay.

Galaway was originally charged with second-degree murder and kidnapping, but accepted a plea deal, said John Kim, prosecuting attorney for Maui County.

On Sept. 1, 2011, Cassman's body was found at Maui's Nakalele Point by officers who responded to calls about a domestic dispute. Galaway bolted from police, survived a leap from a cliff and was arrested the next day.

An autopsy concluded that Cassman died from asphyxiation.

Robert Rivera, first deputy prosecuting attorney, said, "At first we could not figure out why Galaway was driven to kill, but when we read about abusive men, there are two reasons men are abusive: they choose to be abusive and they can be abusive.

"We try to make sense of things," he said, "but there is no motive in this case."